EFFECTS OF 3D PRINTING PROCESSING PARAMETERS ON MECHANICAL PROPERTIES OF POLYMERIC MATERIALS

Additive manufacturing has been used for many years to create complex shapes and designs that would otherwise be difficult for traditional machining methods to produce. However, little is known about the mechanical properties of objects produced via such methods and, as a result, these objects rarely find their way into structural applications. To better understand the applicability of additive manufacturing in structural applications, specimens were created using variations of 3D build parameters. Influence of basic parameters such as build direction, infill pattern (±45-degree lines, longitudinal lines, transverse lines, concentric lines), and printed layer height (0.2 mm, 0.16 mm, 0.1 mm) were explored on several types of polymers, to include PLA, PETG, and polycarbonate. Tensile testing was used to evaluate the effects of the 3D printing parameters on mechanical properties. Regardless of material tested, infill raster patterns that were oriented in line with applied stress axis resulted in samples with superior strength and strain properties. Additionally, printing with smaller layer heights produced denser samples, which generally exhibited better mechanical properties compared to samples printed with larger layer heights. While some mechanical trends held true across material type, others did not, indicating there are no ideal print settings that can be universally applied to all materials.Lieutenant, United States NavyApproved for public release. Distribution is unlimited